xref: /third_party/curl/lib/vauth/cram.c (revision 13498266)
1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 * RFC2195 CRAM-MD5 authentication
24 *
25 ***************************************************************************/
26
27#include "curl_setup.h"
28
29#ifndef CURL_DISABLE_DIGEST_AUTH
30
31#include <curl/curl.h>
32#include "urldata.h"
33
34#include "vauth/vauth.h"
35#include "curl_hmac.h"
36#include "curl_md5.h"
37#include "warnless.h"
38#include "curl_printf.h"
39
40/* The last #include files should be: */
41#include "curl_memory.h"
42#include "memdebug.h"
43
44
45/*
46 * Curl_auth_create_cram_md5_message()
47 *
48 * This is used to generate a CRAM-MD5 response message ready for sending to
49 * the recipient.
50 *
51 * Parameters:
52 *
53 * chlg    [in]     - The challenge.
54 * userp   [in]     - The user name.
55 * passwdp [in]     - The user's password.
56 * out     [out]    - The result storage.
57 *
58 * Returns CURLE_OK on success.
59 */
60CURLcode Curl_auth_create_cram_md5_message(const struct bufref *chlg,
61                                           const char *userp,
62                                           const char *passwdp,
63                                           struct bufref *out)
64{
65  struct HMAC_context *ctxt;
66  unsigned char digest[MD5_DIGEST_LEN];
67  char *response;
68
69  /* Compute the digest using the password as the key */
70  ctxt = Curl_HMAC_init(Curl_HMAC_MD5,
71                        (const unsigned char *) passwdp,
72                        curlx_uztoui(strlen(passwdp)));
73  if(!ctxt)
74    return CURLE_OUT_OF_MEMORY;
75
76  /* Update the digest with the given challenge */
77  if(Curl_bufref_len(chlg))
78    Curl_HMAC_update(ctxt, Curl_bufref_ptr(chlg),
79                     curlx_uztoui(Curl_bufref_len(chlg)));
80
81  /* Finalise the digest */
82  Curl_HMAC_final(ctxt, digest);
83
84  /* Generate the response */
85  response = aprintf(
86    "%s %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
87    userp, digest[0], digest[1], digest[2], digest[3], digest[4],
88    digest[5], digest[6], digest[7], digest[8], digest[9], digest[10],
89    digest[11], digest[12], digest[13], digest[14], digest[15]);
90  if(!response)
91    return CURLE_OUT_OF_MEMORY;
92
93  Curl_bufref_set(out, response, strlen(response), curl_free);
94  return CURLE_OK;
95}
96
97#endif /* !CURL_DISABLE_DIGEST_AUTH */
98